Vacuum cleaner cleaning head

ABSTRACT

A vacuum cleaning head for a vacuum cleaner includes structure for inducing vortices in the incoming air travelling between the sole plate and the surface to be cleaned. The vortices assist in entraining dust and dirt particles raised from the surface to be cleaned by a cleaning implement which may be a brush, beater bar or the like. The axis of the vortices is substantially parallel to the surface to be cleaned and the vortices b ring the rotating air substantially adjacent to and preferably in contact with the surface to be cleaned.

FIELD OF THE INVENTION

[0001] This invention relates to the field of vacuum cleaners. Inparticular, the invention relates to air flow in the cleaning headportion of a vacuum.

BACKGROUND OF THE INVENTION

[0002] Vacuum cleaners involve a suction fan typically driven by anelectric motor. The suction fan creates a negative pressure drawingsignificant amounts of air at relatively high flow rates through acleaning head and into a dirt collection chamber. Typically the cleaninghead includes a rotating cleaning implement. The rotating cleaningimplement typically involves bristles but may also involve beater barsand the like. The purpose of the rotating cleaning element is to impactthe surface being cleaned such as floors, carpet, upholstery and thelike so as to mechanically agitate the surface and cause dirt particlesto be raised up from the surface to be cleaned. Once the particles arelifted from the surface to be cleaned, then the intention is that suchdirt particles should become entrained in the air being drawn into thesuction fan.

[0003] The cleaning head of a vacuum typically defines a sole plate. Thesole plate is arranged generally opposite to and substantially parallelto the surface to be cleaned. The sole plate defines a gap between theleading edge of the sole plate and the surface to be cleaned. Air beingdrawn in by the suction fan typically passes below the leading edge ofthe sole plate travelling rearwardly toward the cavity in which thebrush is located. Some of the incoming air passes below the axis of thecleaning implement more or less along the surface to be cleaned and thenpasses upwardly into the vacuum inlet or whatever tubing connects thevacuum inlet to the suction fan. This air flows in a relativelyorganized fashion. The air travels essentially in a direction parallelto the surface to be cleaned. This air stream entrains the liberateddirt particles and carries those particles into the suction conduit.

[0004] In many vacuum cleaning heads the cavity housing the cleaningimplement is relatively large compared to the circumference of thecircle defined by the radially outermost rotating cleaning elements. Thegap between the cleaning head and the circle defined by the rotatingelements thus provides another path for incoming air being drawn intothe suction conduit. However, air passing above the axis of the cleaningimplement, not passing along or substantially next to the surface to becleaned is not aiding in entraining particles which have been liftedfrom the surface to be cleaned. Thus, in large measure this air is notproductively assisting the cleaning process.

[0005] The remainder of the incoming cleaning air passes beneath theaxis of the rotating brush and above the surface to be cleaned.

[0006] It would be desirable, if steps were taken to modify the flowcharacteristics of the incoming air to assist in entraining dirtparticles which have been lifted from the surface to be cleaned by thecleaning element. In addition, it would be desirable to reduce air flowwhich does not entrain dust particles which have been raised.

SUMMARY OF THE INVENTION

[0007] In accordance with this invention, a vacuum cleaner includes acleaning head. The cleaning head has a housing and the housingoptionally defines a brush cavity for containing an optional rotatingcleaning implement and a vacuum inlet aperture. The housing has a soleplate which, in use, will be adjacent to a surface to be cleaned. Thesole plate is adapted to direct air toward the vacuum inlet aperture.The cleaning head includes vortex inducing structure for creatingvortical flow in the air being directed toward the vacuum inletaperture.

[0008] In a preferred embodiment of the invention, the vacuum cleaninghead include structure for inducing a plurality of vortices in the airbeing directed toward the vacuum inlet aperture. Most preferably, thevortices are oriented so that the axis of rotation of each vortex issubstantially parallel to the surface to be cleaned so that air movingin the vortices travels closely adjacent the surface to be cleaned.

[0009] In another embodiment of the invention, the invention includes amethod of entraining dirt particles in an air stream of a vacuumcleaner. The method includes the step of causing inlet air to be drawnbetween a sole plate of a vacuum cleaning head and a surface to becleaned and directing that air toward a vacuum inlet aperture. Themethod also includes the steps of inducing vortices in the incoming airto assist in entraining dust particles. Preferably, the vorticescreated, cause the incoming air to rotate about axes which are parallelto the surface to be cleaned and the vortices are closely adjacent tothe surface to be cleaned.

[0010] In a preferred aspect of the method, the method further includesthe step of inhibiting air flow through a secondary route between arotating cleaning element and a cavity in the cleaning head housing therotating element.

DETAILED DESCRIPTION OF THE DRAWINGS

[0011] A better understanding of the invention can be obtained fromreference to the following description of a preferred embodiment of theinvention, and in which:

[0012]FIG. 1 illustrates the general arrangement of parts in a prior artvacuum cleaner;

[0013]FIG. 2 is a cross-sectional view through the cleaning head of theprior art device illustrated in FIG. 1;

[0014]FIG. 3 is a view similar to FIG. 2 showing a cross-section througha cleaning head in accordance with a first embodiment of this invention;

[0015]FIG. 4 is a bottom view of a portion of the cleaning head of FIG.3;

[0016]FIG. 5 is a front view of the cleaning head of FIG. 4;

[0017]FIG. 6 is a view of one of the vortex inducing elements of thecleaning head of FIG. 3 showing a first form of vortex produced;

[0018]FIG. 7 is a view similar to FIG. 6 showing an alternate form ofvortex to be produced by the vortex inducing element;

[0019]FIG. 8 is a diagrammatic illustration of vortices induced by thestructure shown in FIG. 7;

[0020]FIGS. 9a-e are front elevational views of the lower portion of acleaning head including vortex inducers according to the instantinvention;

[0021]FIG. 10 is a front perspective view of a sole plate includingvortex inducers according to the instant invention;

[0022]FIG. 11 is a bottom plan view of the sole plate of FIG. 11 showingthe vortex inducers; and, FIG. 12 is a perspective view of the bottom ofthe sole plate of FIG. 11.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0023] The general arrangement for a vacuum cleaner is illustrated inFIG. 1. Generally speaking, a vacuum cleaner 10 comprises a cleaninghead 12, a body portion 14 and a handle 16. The body portion 14 mayinclude a motor 18 which drives a vacuum suction fan 20. The cleaninghead 12 defines a suction inlet conduit 22. The suction inlet conduit 22of the cleaning head 12 is joined to a suction tube 24 in the bodyportion 14. The suction tube 24 of the body portion 14 terminates in anoutlet 26. As shown in FIG. 1, the vacuum 10 is placed to begin cleaningof a surface, in this case a carpet 30. Upon operation, the suction fan20 draws air into the vacuum 10. The air passes beneath a sole plate 32in a generally rearwardly direction as indicated by arrow 34. The airwill be drawn into the inlet conduit 22 and pass into the suction tube24. Upon exiting the outlet 26, the air, as shown by arrow 50, entersthe interior of the housing 14. The interior of the housing 14 mayseparate the dirt from the air by means of various filter means or byusing cyclonic action or the like. Advantageously, the vacuum includes afinal filter 52 located just before the suction fan 20. Air, as shown bythe arrows 54, enters the final filter 52, passes through the suctionfan 20 and then passes over the motor 18 as shown by arrows 56 so thatthe motor is cooled. Air is then exhausted from the vacuum through anoutlet port as shown by arrow 58.

[0024] In FIG. 1, the vacuum illustrated is what is referred to as anupright vacuum. In another arrangement of these basic parts, a vacuummay be referred to as a canister vacuum. A canister vacuum will have apower head similar to the power head 12 illustrated in FIG. 1. However,the motor 18, the fan 20 and the dirt collection means may be located ina separate module referred to as a canister. In a canister vacuum ahandle is attached to the cleaning head 12 rather than to the canisterand suitable conduit means are supplied to conduct the air from theconduit 22 in the cleaning head to the tube 24 within the canister.

[0025]FIG. 2 is an enlarged view of a portion of the cleaning head 12 ofthe prior art device of FIG. 1. The cleaning head 12 defines a cavity 60for containing a rotating cleaning implement. As shown in FIG. 2, therotating cleaning implement is a brush 62 having a plurality of radiallyoutwardly extending bristles 64. The bristles 64 may be arrayed aboutthe surface of the brush 62 in any convenient fashion. Typically thesebristles are arranged in two rows which extend in spiral fashion alongthe surface of the brush 62. The brush 62 rotates about an axis 66. Asshown in FIG. 2 the brush is rotating counterclockwise as indicated byarrow 68.

[0026] As the brush rotates about the axis 66, the radially outwardlylimit of the bristles 64 describe a circle concentric on axis 66. Thiscircle is illustrated by dotted line 70 in FIG. 2. It will be observedthat there is substantial clearance between the circle 70 and thesurface of the brush cavity 60. This, in turn, means that as the airflows rearwardly as indicated by arrow 34, the air stream splits intotwo streams, one indicated by arrow 36 and one indicated by arrow 38.The air indicated by arrow 38 travels in the annular gap between thecircle 70 and the surface of the cavity 60 above the axis 66. The airindicated by arrow 36 passes substantially along the carpet 30 beneaththe axis 66 of the rotating brush. The two air streams converge asindicated by the arrows 38 b and 36 b where the air then enters an inletaperture 80. The two air streams merge as indicated by the arrow 82 andpass along the suction inlet conduit 22.

[0027] Air indicated by the arrows 38 and 38 b does not pass alongcarpet 30 and thus does not materially assist in entraining particleswhich have been raised from the carpet 30. The second component of theair indicated by the arrows 36 and 36 b passes in a direction which isgenerally parallel to the carpet 30 and serves to entrain particlesraised up from the carpet 30 by the action of the rotating brush 62.

[0028]FIG. 3 is a view similar to FIG. 2 and like parts have been givensimilar numbers but with the prescript 1. Thus, the cleaning head 112 ofthe vacuum cleaner 110 in accordance with this preferred embodiment ispositioned adjacent a surface to be cleaned, a carpet 130. The cleaninghead 112 comprises a cavity 160. The cavity 160 accommodates a rotatingbrush 162 having a plurality of bristles 164. The radially outwardlylimit of the bristles 164 when rotating, define a circle 170. The brush162 rotates about an axis 166. The brush rotates counterclockwise asindicated by arrow 168. The cleaning head 112 includes a sole plate 132which is generally adjacent to the carpet 130. The cleaning head 112also has a suction inlet conduit 122 having a vacuum inlet aperture 180.

[0029] From review of FIG. 3, it will be noted, that the circle 170described by the tips of the bristles 164 is located substantiallyadjacent the surface of the cavity 160. The clearance between the circle170 and the cavity 160 is reduced to a convenient minimum. The clearancemust be such that the tips of the bristles when the brush is installed,in its new condition, do not strike the surface of the cavity 160 as thebrush rotates. However, it is desirable to reduce the clearance to anacceptable minimum so as to inhibit any flow in the secondary flow routeas indicated in the prior art in connection with arrows 38 and 38 b.Thus, in the embodiment illustrated in FIG. 4, for a given in-flow rateas shown at 134, more of the air is caused to pass adjacent to thecarpet 130 by the virtual elimination of the secondary air flow routethrough the clearance gap between the surface of the cavity 160 and thebrush 162. Because there is substantially no flow adjacent the surfaceof the cavity 160, virtually all of the air passes in the generaldirection indicated by arrow 137, below the axis of rotation 166 of thebrush 162 and adjacent the carpet 130. The air then passes, as indicatedby arrow 183, into the inlet aperture 180.

[0030] The cleaning head 112 further includes structure 190 for inducingat least one vortex in the incoming air stream. The vortex inducingstructure 190 may be located on the sole plate 132 and is intended toinduce at least one vortex in the air being directed toward the vacuuminlet aperture 180 such that the airflow passing over the surface to becleaned is substantially vortical. The ratio of the width Wo of slots200 to the width Ws of the vortex inducer 190 preferably varies from 4:1to 1:4, preferably from 3:1 to 1:3 more preferably from 1:2 to 2:1 andmost preferably, is about 1:1. Similarly, the ratio of the height Ho ofslots 200 to the height Hs of the vortex inducer 190 preferably variesfrom 4:1 to 1:4, preferably from 3:1 to 1:3 more preferably from 2:1 to1:2 and most preferably, is about 1:1.

[0031] In the preferred embodiment shown in FIGS. 9b and 10-12, theratio of the width Wo of slots 200 to the width Ws of the vortex inducer190 is 1:1 and the ratio of the height Ho of slots 200 to the height Hsof the vortex inducer 190 is 1:1. Alternate workable profiles are shownin FIGS. 9a-9 e. In the preferred embodiment shown in FIG. 9a, the ratioof the width Wo of slots 200 to the width Ws of the vortex inducer 190is 1:2 and the ratio of the height Ho of slots 200 to the height Hs ofthe vortex inducer 190 is 1:1. In the preferred embodiment shown in FIG.9c, the ratio of the width Wo of slots 200 to the width Ws of the vortexinducer 190 is 2:1 and the ratio of the height Ho of slots 200 to theheight Hs of the vortex inducer 190 is 1:1. In the preferred embodimentshown in FIG. 9d, the ratio of the width Wo of slots 200 to the width Wsof the vortex inducer 190 is 1:1 and the ratio of the height Ho of slots200 to the height Hs of the vortex inducer 190 is 3:2. In the preferredembodiment shown in FIG. 9e, the ratio of the width Wo of slots 200 tothe width Ws of the vortex inducer 190 is 1:1 and the ratio of theheight Ho of slots 200 to the height Hs of the vortex inducer 190 is3:1.

[0032] As shown from the forgoing examples, when vortex inducers 190 arenarrower than the slot 200 between them, effective vortices can also becreated (see FIG. 9c). Alternately, when the vortex inducers may bewider (e.g. twice as wide) than the slot between them, effectivevortices can also be created (see FIG. 9a).

[0033] Preferably, a plurality of vortices are induced along essentiallythe entire length of the front of the vacuum cleaner. Thus, the airdrawn in by the suction fan passes between the sole plate 132 and thecarpet 130, as indicated by arrow 134. The air passes through the vortexinducing structure 190 under the rotating brush 162 and into theaperture 180.

[0034]FIG. 4 illustrates a portion of the sole plate 132 of the cleaninghead 112 illustrated in FIG. 3. From reference to FIG. 4, it will benoted that the vortex inducing structure 190 comprises a plurality ofblade members 190 a. There are 12 such blade members 190 a shown in FIG.4 which are aligned to interact with the incoming air flow as indicatedby the arrows 134. Most of the air being drawn into the vacuum inletport 182 will enter the cleaning head 112 adjacent the leading edge 113.Wheels or other structure in the cleaning head 112 may inhibit airflowing in from the sides of the cleaning head 112. As shown in FIG. 4,the air stream indicated by arrows 134 is flowing substantiallyrearwardly from the leading edge 113 toward the inlet aperture 182. Eachof the individual blade members 190 a creates a vortex downstream of theblade member 190 a. This is indicated generally by the lines 194.

[0035]FIG. 5 illustrates the cleaning head 112 from the front, locatedadjacent the carpet 130.

[0036]FIGS. 6 and 7 illustrate two slightly differently shaped blademembers 190 a and 190 b. The shape of the blade members can be any shapewhich creates a downstream vortex in the air stream passing by the blademember 190 a or 190 b respectively.

[0037] As shown in FIG. 6, the blade member 190 a creates a singledownstream vortex which may be substantially aligned with the generalaxis of symmetry 191 of the blade member 190 a. In this case, the airstreams passing along either side face of the blade member 190 a meet toform the vortex 194. The vortex 194 spins about an axis 195 which isaligned with axis 191. The precise shape, location and configuration ofthe vortex 194 will dependent on the particular shape and configurationof the blade member 190 a. A single vortex 194 for each such blademember 190 a has been illustrated in FIG. 4.

[0038]FIG. 7 illustrates an alternately shaped blade member 190 b. Blademember 190 b produces a pair of vortices on either side of the generalaxis of symmetry 193 of the blade member 190 b. These vortices are shownas 196 a and 196 b. The vortices 196 a and 196 b are caused to spinabout axes 198 a and 198 b respectively. For reasons which will bediscussed below, advantageously, the direction of spin in vortex 196 ais opposite to the direction of spin in the vortex 196 b.

[0039] The vortex 194 is spinning about the axis 195 while the vortices196 a and 196 b are spinning about their respective axes 198 a and 198b. All three of the axes 195, 198 a and 198 b, lie substantiallyparallel to the carpet 130. Thus, the axes of spin of the vortices maybe said to coincide with the arrow 137 showing the general direction ofair flow in FIG. 3. Each vortex is therefore spinning about an axiswhich is substantially parallel to the carpet 130. The axis 137, 198 aand 198 b are adjacent the carpet 130. As the air spins about itsrespective axis, in the vortices as discussed above, the air impacts thefloor with relatively high velocity. Because of the spinning of the airin the vortices, there is highly turbulent flow of the air adjacent tothe carpet 130. Thus, there is substantially increased turbulence at theflow indicated by arrow 137 in FIG. 3 as opposed to the flow asindicated at arrow 36 in prior art devices. The air flow has a rearwardcomponent generated by the suction fan. In addition, the air has aspiralling component generated by the vortex inducing structure 190.This increased turbulence in the air assists in entraining dirtparticles which have been liberated from the carpet 130 by the brush164.

[0040] Conveniently, the brush 164 may be formed similar to brushescommonly used in the vacuum art. Such brushes contain a plurality ofbristles arranged in two rows. The rows are arranged in spiral fashionalong the length of the brush 162. Thus, each vortex 194, 196 a or 196 brespectively is not effected by the bristles 164 of the brush 162 excepton those occasions when a bristle is directly aligned with theparticular member 190 a or 190 b, respectively. If there are two rows ofbristles on the brush 162, then this interruption of the vortex willoccur only momentarily, twice during each revolution of the brush 162.The vortex, however, will remain in place during the remainder of arotation of the brush 162.

[0041] Preferably, as shown in FIG. 7, the vortex inducing structure 190includes blade members 190 b which produce a pair of counter rotatingvortices 196 a and 196 b. These are shown in the front view in FIG. 5.One vortex 196 a and one vortex 196 b is induced by each individualblade member 190 b. However, adjacent vortices 196 a and 196 b betweenadjacent blade members 196 b are rotating in complimentary directions.This is illustrated in FIG. 8. In FIG. 8, the vortices 196 a and 196 bfor each of two blade members 190 b are illustrated. The outer elementsof the adjacent vortices are moving in the same direction. Thus, theturbulence of each vortex does not dissipate but rather supplements thenext adjacent vortex.

[0042] The plurality of vortices formed by the vortex inducing structure190 serves to assist in entraining dirt particles which are raised fromthe carpet 130 by the brush 162. The vortex may break up before the airstream enters the vacuum inlet port 182. However, once dirt is entrainedin the air flow, the dirt tends to stay entrained. By utilizing thevortices as explained herein, enhanced entrainment of the dirt raised bythe cleaning implement is achieved.

[0043] The vortex inducing structure 190 has been explained inassociation with a plurality of individual members which are essentiallytear dropped shaped. Many other forms of vortex inducing structure maybe utilized.

[0044] The purpose of the vortex is to assist in entraining dirt raisedby the rotating cleaning element. Thus, the vortex inducing structurecan be located anywhere as convenient provided it produces vorticeswhich are effective to entrain dirt. As shown in FIG. 3, the vortexinducing structure can be attached to the sole plate 132 just forward ofthe cavity 160 for containing the brush. However, the vortex inducingstructure can be mounted anywhere as desired.

[0045] In order to assist in maintaining the front of sole plate 132 atthe desired distance above the surface to be cleaned, wheels, glides orthe like may be provided, preferably proximate leading edge 113, as isknown in the art. In the preferred embodiment of FIGS. 10-12, wheelwells 202 are provided adjacent opposed lateral sides of sole plate 132.

[0046] While the invention has been discussed in the context of certainpreferred embodiments, these embodiment are illustrative only. For thefull scope of the invention, reference should be made to the followingclaims. It will be appreciated that cleaning head 112 may be utilizedwithout the operation of brush 162. Further, in some embodiments,cleaning head need not include brush 162 or other like cleaningimplement.

We claim:
 1. A cleaning head having a front end comprising a sole plate,a vacuum inlet aperture, and vortex inducing structure for inducingvortical flow in air travelling toward said vacuum inlet aperture. 2.The cleaning head of claim 1 wherein said vortex inducing structureincludes a plurality of vortex inducing members for inducing a pluralityof vortices across essentially all of the front of the cleaning head. 3.The cleaning head of claim 2 wherein said vortices produced by saidplurality of vortex inducing members rotate about a respective vortexaxis and the axes of said plurality of vortices extend substantiallyparallel to said surface to be cleaned.
 4. The cleaning head of claim 3wherein said plurality of vortex inducing members are blade members andeach of said blade members creates at least one vortex.
 5. The cleaninghead of claim 4 wherein each of said blade members creates a pluralityof vortices.
 6. The cleaning head of claim 5 in which each blade memberproduces two vortices and the air in the two vortices rotates inopposite directions.
 7. The cleaning head of claim 1 further comprisinga cleaning element.
 8. The cleaning head of claim 7 wherein the cleaningelement comprises a rotating cleaning implement and said cleaningimplement rotates about an axis and said cleaning head comprises meansfor inhibiting flow of air between said rotating cleaning implement anda surface of said cavity for housing said cleaning implement.
 9. Thecleaning head of claim 1 wherein said vortex inducing structure includesa plurality of vortex inducing members for inducing a plurality ofvortices spaced along at least a portion of the front of the vacuumcleaner head and defining slots openings between adjacent vortexinducing members and the ratio of the width of the openings to the widthof the vortex inducing members varies from 4:1 to 1:4 and the ratio ofthe height of the openings to the height of the vortex induceing membersvaries from 4:1 to 1:4.
 10. The cleaning head of claim 1 wherein saidvortex inducing structure includes a plurality of vortex inducingmembers for inducing a plurality of vortices spaced along at least aportion of the front of the vacuum cleaner head and defining slotsopenings between adjacent vortex inducing members and the ratio of thewidth of the openings to the width of the vortex inducing members variesfrom 3:1 to 1:3 and the ratio of the height of the openings to theheight of the vortex induceing members varies from 3:1 to 1:3.
 11. Thecleaning head of claim 1 wherein said vortex inducing structure includesa plurality of vortex inducing members for inducing a plurality ofvortices spaced along at least a portion of the front of the vacuumcleaner head and defining slots openings between adjacent vortexinducing members and the ratio of the width of the openings to the widthof the vortex inducing members varies from 2:1 to 1:2 and the ratio ofthe height of the openings to the height of the vortex induceing membersvaries from 2:1 to 1:2.
 12. The cleaning head of claim 1 wherein saidvortex inducing structure includes a plurality of vortex inducingmembers for inducing a plurality of vortices spaced along at least aportion of the front of the vacuum cleaner head and defining slotsopenings between adjacent vortex inducing members and the ratio of thewidth of the openings to the width of the vortex inducing members issubstantially 1:1 and the ratio of the height of the openings to theheight of the vortex induceing members is substantially 1:1.
 13. Amethod of entraining dirt for use in a vacuum cleaner having a vacuumcleaning head, said vacuum cleaning head having a sole plate and avacuum inlet aperture causing air to pass in an air stream between saidcleaning head and a surface to be cleaned, and inducing vortical flow insaid air stream as said air travels toward said vacuum inlet aperture.14. The method of claim 13 wherein said cleaning head includes a cavityfor containing a cleaning implement and a cleaning implement in thecavity and the method further comprises the step of inhibiting the flowof air between said cleaning implement and said cavity.
 15. The methodof claim 13 further comprising the step of inducing a plurality ofvortices in said air stream.
 16. The method of claim 15 in which saidvortices are arranged to spin about respective axes and said axes extendgenerally parallel to said surface to be cleaned.
 17. The method ofclaim 16 in which said vortices are arranged such that the axes ofrotation of said vortices lie substantially adjacent to said surface tobe cleaned so that the air rotating in said vortices is substantiallyadjacent to the surface to be cleaned.